Coral reefs face many challenges to their survival, including the global acidification of seawater as a result of rising carbon dioxide levels in the atmosphere. A new study led by scientists at UC Santa Cruz shows that at least three Caribbean coral species can survive and grow under conditions of ocean acidification more severe than those expected to occur during this century, although the density of their skeletons was lower than normal.
The study took advantage of the unusual seawater chemistry found naturally at sites along the Caribbean coastline of Mexico's Yucatan Peninsula, where water discharging from submarine springs has lower pH than the surrounding seawater, with reduced availability of the carbonate ions corals need to build their calcium carbonate skeletons.
In a two-year field experiment, the international team of researchers transplanted genetically identical fragments of three species of corals to a site affected by the springs and to a nearby control site not influenced by the springs, and then monitored the survival, growth rates, and other physiological traits of the transplants. They reported their findings in a paper published June 26 in Proceedings of the Royal Society B.
"The good news is the corals can survive and deposit calcium carbonate, but the density of their skeletons is reduced, which means the framework of the reef would be less robust and might be more susceptible to storm damage and bioerosion," said Adina Paytan, a research professor at UCSC's Institute of Marine Sciences and corresponding author of the paper.
Read more at University of California - Santa Cruz
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